Arizona weekly enterprise., 1887-11-26
HOW A DOG FOLLOWS TRAIL.
Interesting and Novel Experiments by
 Scientific Investigator.


 Scientific Investigator.
 Dr. G. J. Romanes, by his careful ob- servations and happy generalizations, has made himself the representative of the growing science of comparative psychol- ogy. Dr. Romanes has made an import ant study on the method by which his dog follows the scent of the master. The observations were made on Dr. Romanes' setter bitch, an animal very much at tached to him. They were made on the grounds adjoining his house, and a num- Der of precautions not easily described were taken.
 When Dr. Romanes walks over the ground with his hunting boots on, the dog follows the scent with the greatest readiness. If she is put to the track of stranger she pays no attention to it. The dog was led into the room when preparaS tions were going on for an outing, but instead of Dr. Romanes going out, the gamekeeper (whose scent she follows next after that of Dr. Romanes) went; when set free the animal at first followed the track, but finding that her master was not with the gamekeeper, returned.
 The next experiment was a very in genious one: Twelve men walked in h. dian file, so that they all trod the same footsteps, thus producing a conglomerate of olfactory impressions. Dr. Romanes headed the company, so that the traces of his steps should be most obliterated; and, after walking thus 200 yards, the first six men walked in one direction, the last six ia another. The dog quickly ran along the route followed by the twelve, over shot the point of division, but soon re- turned and followed the direction taken by the six headed by Dr. Romanes.
 4 number of experiments were made to ascertain what part of Dr. Romanes' person or of his apparel gave the clew to the animal. It was suspected to be the l hunting boots, and this proved correct. A stranger put on these boots, and the dog eagerly followed the scent; and, con | trariwise, when Dr. Romanes put on the strangers boots the animal was indiffer- ent to his track. Further experiments were made to locate the source of the scent in the boots. The dog did not fol- | bare feet. When Dr. Romanes walked in bare feet the dog followed the trace, but less eagerly than usual, ard with
 much hesitation. Again, the animal did not follow Dr. Romanes when he put on new shooting boots. Next single sheet of brown paper was glued to the soles of his usual hunting boots. The dog did not catch the trail until he came to a
 place where, as Dr. RomaneS had previ-
 ously noted, few square milhmetres of the paper had come off. When her
 master walked in new cotton socks, the
 trail was lazily followed, and soon given
 up. With woolen socks worn all day I the result was the same.
 Dr. Roranes next walked fifty yard:
 in shooting boots; then 300 yards in hi:
 stocking soles, carrying his boots; theI
 3SO in his bare feet. The animal caugh
 the scent and followed it unhesitatingly
 through the whole distance, though thu
 trace left by stockings or bare feet alon'
 was not sufficient to guide the animal
 The next was modification of the last
 Dr. Romanes and stranger entered
 carriage and drove for several hundred
 wards. The former, in his hunting boots
 then alighted and walked fifty yards
 whereupon he re-entered the carriage
 and the stranger walked the next 20 yards; the dog. when shown the track ! Tdu lilt W ilOlG SOO 1Sio "AOAAOoS P0AAAic [, The experiment was repeated with an other stranger with the same result To test the power which the dog had c selecting the distinctive odor accompany . ing her master from other odors. Dl q Ronnanes soaked his hunting boots i aniseseed oil. The odor was so stron l that friend could follow the track a
 hour later by the odor of the oil; yet tn a dog was not confused except that st s hesitated about the first few steps, bJ
 then pursued as usual.
 The next test was directed toward a P certaining whether the animal could di n tinguish her master by odors emanatir :, from other portions of his person. D n Romanes, after pursuing zigzag cour o just trodden over by number of foo
 steps, hid behind wall, with his ey it just visible. The animal went at once q the hiding place. Again, he hid in V ditch, with only the top of his head wis 7. ble. At 200 yards the dog detected h d master, and went to him directly.
 A From these tests Dr. Ronlanes co fe cludes that the dog distinguishes hi 70 from all others by the odor of his boot
 and does not distinguish him in his nak
 feet. The odor is probably emitted by t
 feet, but must be mixed with that of sh ar leather to be of service to the dog. III q is doubtless a matter of education; h T. the dog been used to following her mast It when without shoes, the animal wou pa have learned to follow him thus. T ,t characteristic odor cannot penetrate re sheet of brown paper, but a few squs ly millimeters of surface is sufficient to gi ,e the dog the clew. The animal is ready Id be guided by inference as well as by p le ception, but the inference is instantaneol ns Lastly, not only the feet (through re boots), but the whole body, emits an ot ne that the dog can distinguish in mass d. others. This odor is recognized at gr at distances to windward, or in ca ve weather in any direction; it is not ov id powered by aniseseed oil or by the fo n- prints of another.-Science.